Mushkin passed along a dual-module 8GB (that is, 16GB total) kit of its Redline DDR4-2666 memory just in time for our Z370 launch. (Specifically, this kit is part number MRA4U266GHHF8GX2.) Alas, none of the boards we originally tested at the time of that launch was (by our admittedly aggressive memory-overclocker standards) “good enough” to use as a test platform. Months passed before we finally settled on a board that’s still a little shy on memory overclocking compared to the Z270 platform that preceded it. But, hey, at least we get to test with a faster Coffee Lake CPU...

The full primary timing set of 16-17-17-36 beats standard DDR4-2666 CAS 17 timings while retaining industry-standard 1.20V DDR4 voltage. But those improved timings still require the builder to enable XMP mode. Without enabling XMP, the memory defaults to DDR4-2133 CAS 15. Let's get down to testing it.

Comparison Products

Our greatest concern for fairness was to make sure the Redline 16GB DDR4-2666 would be compared to other kits in the same two-8GB-module configuration. But notice below that one thing remains different for one set: The DDR4-3000 kit has eight 512MB ICs on each side rather than eight 1024GB ICs on just one side. Eight ICs make up a 64-bit “rank,” so that for each memory channel, one “dual-rank” module performs similarly to two single-rank modules.

Intel’s memory controller works better with four ranks than with two. Because this performance difference caused confusion in a previous review, we’ve added the “dual rank” tag here for clarity.

We’re expanding outward from our Corsair DDR4-4600 review by switching to a board that supports four DIMMs. MSI’s Z370 Godlike Gaming doesn’t have any memory overclocking advantages over the smaller board used in that review, but it has similar performance scaling and can push several of our kits past DDR4-4000. We’re also holding over the hardware from that review, including our GeForce GTX 1080 and Toshiba/OCZ NVMe SSD.

It's a sad day when $120 for 16GB of RAM is hailed as a budget value. At least $30 if not more over what it's actually worth; 16GB of 2400Mhz was $79 (or less) in early 2017.

Crashman

1464708 said:

It's a sad day when $120 for 16GB of RAM is hailed as a budget value. At least $30 if not more over what it's actually worth; 16GB of 2400Mhz was $79 (or less) in early 2017.

Not exactly hailed except in the exuberant headline modification of our fearless leader: "Decent enough" is just that, a fair price under current market conditions.Memory prices spiked a few months ago, so I can say "at least this isn't January".

kraelic

$120 HAH... it is sold out and $170 now. Probably a promotional stunt to get talked about.

Crashman

48351 said:

$120 HAH... it is sold out and $170 now. Probably a promotional stunt to get talked about.

Our review queue is over two months long, how would they know when we were going to publish?

kraelic

Not sure, just seen the article and saw the big green advertisement button for $120. And clicking the link takes you to see $170. Seems to be a lot of pricing discrepancies in the articles. The button is hard coded? No way to have it do an hourly update for current prices?

For my Dell XPS 8930(Intel Z370 and Intel i7-8700) but it is defaulting to 2133 MHz. Case has been opened with Mushkin but no resolution. Dell support is simply having all sort of excuses not to help me on this front.

I was trying to upgrade the memory(from previous 4 X 8GB) to 4 X 16GB. Previous one was Hynix and Micron and it always worked at 2666 MHz but Mushkin is not working at 2666 MHz but at 2133 MHz. I have no idea how to enable XMP on this mother board. Absolutely no support from Dell.

Crashman

2100418 said:

I have bought it from Amazon. This one:
https://www.amazon.com/gp/product/B01LXN1E9U
For my Dell XPS 8930(Intel Z370 and Intel i7-8700) but it is defaulting to 2133 MHz. Case has been opened with Mushkin but no resolution. Dell support is simply having all sort of excuses not to help me on this front.
I was trying to upgrade the memory(from previous 4 X 8GB) to 4 X 16GB. Previous one was Hynix and Micron and it always worked at 2666 MHz but Mushkin is not working at 2666 MHz but at 2133 MHz. I have no idea how to enable XMP on this mother board. Absolutely no support from Dell.

DDR4-2666 as an SPD value is fairly recent, like a year ago. I'm betting this memory was added to Mushkin's product line before that, hence the need for XMP. Your board probably doesn't have any XMP option at all.

I'd like to point out to less-experienced users that most of the memory we review has a top SPD value of 2133 or 2400, and very little has an top SPD of 2666. Users need a board with XMP to use most higher-speed RAM (such as DDR4-3200) at its rated settings. DDR4-2666 is one of those "buyer beware" spots in between where you'd expect that it should be using SPD, but may require XMP instead, as this RAM does.

phil brinkle

I find this review poor.

chinaman

Defaults to 2666 on my Ryzen 3 setup and I can OC to 2933 via XMP very stable.

Crashman

1852213 said:

I find this review poor.

That's not very helpful

Ashutosh_5

Is this not a good mother board then? What to do? Return this memory chip? which one to buy for this mother board which will work at the speed of 2666 MHz. I don't want to spend a lot of money for this? 64 GB( 4 X 16GB) costs more than $700 and I am not getting the right speed.

8708 said:

2100418 said:

I have bought it from Amazon. This one:
https://www.amazon.com/gp/product/B01LXN1E9U
For my Dell XPS 8930(Intel Z370 and Intel i7-8700) but it is defaulting to 2133 MHz. Case has been opened with Mushkin but no resolution. Dell support is simply having all sort of excuses not to help me on this front.
I was trying to upgrade the memory(from previous 4 X 8GB) to 4 X 16GB. Previous one was Hynix and Micron and it always worked at 2666 MHz but Mushkin is not working at 2666 MHz but at 2133 MHz. I have no idea how to enable XMP on this mother board. Absolutely no support from Dell.

DDR4-2666 as an SPD value is fairly recent, like a year ago. I'm betting this memory was added to Mushkin's product line before that, hence the need for XMP. Your board probably doesn't have any XMP option at all.
I'd like to point out to less-experienced users that most of the memory we review has a top SPD value of 2133 or 2400, and very little has an top SPD of 2666. Users need a board with XMP to use most higher-speed RAM (such as DDR4-3200) at its rated settings. DDR4-2666 is one of those "buyer beware" spots in between where you'd expect that it should be using SPD, but may require XMP instead, as this RAM does.

Crashman

2100418 said:

Is this not a good mother board then? What to do? Return this memory chip? which one to buy for this mother board which will work at the speed of 2666 MHz. I don't want to spend a lot of money for this? 64 GB( 4 X 16GB) costs more than $700 and I am not getting the right speed.

8708 said:

2100418 said:

I have bought it from Amazon. This one:
https://www.amazon.com/gp/product/B01LXN1E9U
For my Dell XPS 8930(Intel Z370 and Intel i7-8700) but it is defaulting to 2133 MHz. Case has been opened with Mushkin but no resolution. Dell support is simply having all sort of excuses not to help me on this front.
I was trying to upgrade the memory(from previous 4 X 8GB) to 4 X 16GB. Previous one was Hynix and Micron and it always worked at 2666 MHz but Mushkin is not working at 2666 MHz but at 2133 MHz. I have no idea how to enable XMP on this mother board. Absolutely no support from Dell.

DDR4-2666 as an SPD value is fairly recent, like a year ago. I'm betting this memory was added to Mushkin's product line before that, hence the need for XMP. Your board probably doesn't have any XMP option at all.
I'd like to point out to less-experienced users that most of the memory we review has a top SPD value of 2133 or 2400, and very little has an top SPD of 2666. Users need a board with XMP to use most higher-speed RAM (such as DDR4-3200) at its rated settings. DDR4-2666 is one of those "buyer beware" spots in between where you'd expect that it should be using SPD, but may require XMP instead, as this RAM does.

Keep using it at DDR4-2133? Mushkin didn't spec it wrong so it's not defective. The PC you own was not likely designed for XMP. We have reviews. Our review shows a CPU-Z table that's accurate enough for the average user to see it's only rated DDR4-2666 when using XMP. Even if Mushkin went all out on a publicity campaign to spread the word about XMP vs JEDEC SPD table settings, sellers wouldn't relay that message. But, we have reviews.

Ashutosh_5

What does SPD means? What does XMP means?

8708 said:

2100418 said:

Is this not a good mother board then? What to do? Return this memory chip? which one to buy for this mother board which will work at the speed of 2666 MHz. I don't want to spend a lot of money for this? 64 GB( 4 X 16GB) costs more than $700 and I am not getting the right speed.

8708 said:

2100418 said:

I have bought it from Amazon. This one:
https://www.amazon.com/gp/product/B01LXN1E9U
For my Dell XPS 8930(Intel Z370 and Intel i7-8700) but it is defaulting to 2133 MHz. Case has been opened with Mushkin but no resolution. Dell support is simply having all sort of excuses not to help me on this front.
I was trying to upgrade the memory(from previous 4 X 8GB) to 4 X 16GB. Previous one was Hynix and Micron and it always worked at 2666 MHz but Mushkin is not working at 2666 MHz but at 2133 MHz. I have no idea how to enable XMP on this mother board. Absolutely no support from Dell.

DDR4-2666 as an SPD value is fairly recent, like a year ago. I'm betting this memory was added to Mushkin's product line before that, hence the need for XMP. Your board probably doesn't have any XMP option at all.
I'd like to point out to less-experienced users that most of the memory we review has a top SPD value of 2133 or 2400, and very little has an top SPD of 2666. Users need a board with XMP to use most higher-speed RAM (such as DDR4-3200) at its rated settings. DDR4-2666 is one of those "buyer beware" spots in between where you'd expect that it should be using SPD, but may require XMP instead, as this RAM does.

Keep using it at DDR4-2133? Mushkin didn't spec it wrong so it's not defective. The PC you own was not likely designed for XMP. We have reviews. Our review shows a CPU-Z table that's accurate enough for the average user to see it's only rated DDR4-2666 when using XMP. Even if Mushkin went all out on a publicity campaign to spread the word about XMP vs JEDEC SPD table settings, sellers wouldn't relay that message. But, we have reviews.

Crashman

2100418 said:

What does SPD means?
What does XMP means?

SPD mean "Serial Presence Detect", it's a little IC on the memory that stores a table, that the motherboard reads, to determine the memory frequency and latency. XMP means "Intel Extreme Memory Profiles" (yes, the initials are wrong, Intel does that), which is an additional set of table values for not standard settings.

XMP is an overclocking technology. Most boards that don't support overclocking, don't support XMP.

You shouldn't need to know this just to buy DDR4-2666. After all, DDR4-2666 has been standardized. But it was standardized long after the original DDR4 specs. So for a while, the only way to get DDR4-2666 was by XMP. And now you, the buyer, are in the weird position in this weird place in history where DDR4-2666 is available in both versions, being programmed either way, depending on the product you purchase.

But, we have reviews.

Ashutosh_5

Thanks for your great answer...could you please tell me which memory(DDR4) I should buy for my desktop which doesn't require(XMP) or overclocking and it works fine in my case?

8708 said:

2100418 said:

What does SPD means?
What does XMP means?

SPD mean "Serial Presence Detect", it's a little IC on the memory that stores a table, that the motherboard reads, to determine the memory frequency and latency. XMP means "Intel Extreme Memory Profiles" (yes, the initials are wrong, Intel does that), which is an additional set of table values for not standard settings.
XMP is an overclocking technology. Most boards that don't support overclocking, don't support XMP.
You shouldn't need to know this just to buy DDR4-2666. After all, DDR4-2666 has been standardized. But it was standardized long after the original DDR4 specs. So for a while, the only way to get DDR4-2666 was by XMP. And now you, the buyer, are in the weird position in this weird place in history where DDR4-2666 is available in both versions, being programmed either way, depending on the product you purchase.
But, we have reviews.

Crashman

2100418 said:

Thanks for your great answer...could you please tell me which memory(DDR4) I should buy for my desktop which doesn't require(XMP) or overclocking and it works fine in my case?

8708 said:

2100418 said:

What does SPD means?
What does XMP means?

SPD mean "Serial Presence Detect", it's a little IC on the memory that stores a table, that the motherboard reads, to determine the memory frequency and latency. XMP means "Intel Extreme Memory Profiles" (yes, the initials are wrong, Intel does that), which is an additional set of table values for not standard settings.
XMP is an overclocking technology. Most boards that don't support overclocking, don't support XMP.
You shouldn't need to know this just to buy DDR4-2666. After all, DDR4-2666 has been standardized. But it was standardized long after the original DDR4 specs. So for a while, the only way to get DDR4-2666 was by XMP. And now you, the buyer, are in the weird position in this weird place in history where DDR4-2666 is available in both versions, being programmed either way, depending on the product you purchase.
But, we have reviews.

That is a REALLY tough question for someone who doesn't shop for this stuff, considering that we haven't tested any other DDR4-2666 in a couple years. But, there are shopping tools at sites like Crucial and Kingston, where you can look up DDR4-2666 that has your system on their compatibility list.

Ashutosh_5

8708 said:

2100418 said:

Thanks for your great answer...could you please tell me which memory(DDR4) I should buy for my desktop which doesn't require(XMP) or overclocking and it works fine in my case?

8708 said:

2100418 said:

What does SPD means?
What does XMP means?

SPD mean "Serial Presence Detect", it's a little IC on the memory that stores a table, that the motherboard reads, to determine the memory frequency and latency. XMP means "Intel Extreme Memory Profiles" (yes, the initials are wrong, Intel does that), which is an additional set of table values for not standard settings.
XMP is an overclocking technology. Most boards that don't support overclocking, don't support XMP.
You shouldn't need to know this just to buy DDR4-2666. After all, DDR4-2666 has been standardized. But it was standardized long after the original DDR4 specs. So for a while, the only way to get DDR4-2666 was by XMP. And now you, the buyer, are in the weird position in this weird place in history where DDR4-2666 is available in both versions, being programmed either way, depending on the product you purchase.
But, we have reviews.

That is a REALLY tough question for someone who doesn't shop for this stuff, considering that we haven't tested any other DDR4-2666 in a couple years. But, there are shopping tools at sites like Crucial and Kingston, where you can look up DDR4-2666 that has your system on their compatibility list.

Corsair also has a similar kind of memory but it will end up with the same 2133 on my mother board. Crucial and Micron are the same...as my original one was micron...to be on the safer side...i will go with the crucial.com...hopefully it should work out as on my mother board there is no way one can do over clocking or enter the W-X-Y-Z clock settings for the RAM.Special thanks for Crashman for all your help and insights...